Nato-led British peacekeepers have been fired upon as they challenged a group of armed men in Kosovo.
An observation post manned by British peacekeepers was fired upon near the town of Ukmeme.
The 10 men had been trying to cross into the no-man's land separating Kosovo from the rest of Serbia.
No peacekeepers were injured.
The gang, suspected to be ethnic Albanian guerillas battling Serb forces in the volatile Presevo Valley of southern Serbia, then retreated and travelled back across the boundary.
"The 10 unidentified armed men crossed the Ground Safety Zone and fired upon the KFOR (Kosovo Force) soldiers," said a statement.
"The British soldiers did not return fire and withdrew from the area to a more secure location."
No further details were immediately available.